1 //===-- LibStdcpp.cpp -------------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "LibStdcpp.h"
10 
11 #include "lldb/Core/ValueObject.h"
12 #include "lldb/Core/ValueObjectConstResult.h"
13 #include "lldb/DataFormatters/StringPrinter.h"
14 #include "lldb/DataFormatters/VectorIterator.h"
15 #include "lldb/Symbol/ClangASTContext.h"
16 #include "lldb/Target/Target.h"
17 #include "lldb/Utility/DataBufferHeap.h"
18 #include "lldb/Utility/Endian.h"
19 #include "lldb/Utility/Status.h"
20 #include "lldb/Utility/Stream.h"
21 
22 using namespace lldb;
23 using namespace lldb_private;
24 using namespace lldb_private::formatters;
25 
26 namespace {
27 
28 class LibstdcppMapIteratorSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
29   /*
30    (std::_Rb_tree_iterator<std::pair<const int, std::basic_string<char,
31    std::char_traits<char>, std::allocator<char> > > >) ibeg = {
32    (_Base_ptr) _M_node = 0x0000000100103910 {
33    (std::_Rb_tree_color) _M_color = _S_black
34    (std::_Rb_tree_node_base::_Base_ptr) _M_parent = 0x00000001001038c0
35    (std::_Rb_tree_node_base::_Base_ptr) _M_left = 0x0000000000000000
36    (std::_Rb_tree_node_base::_Base_ptr) _M_right = 0x0000000000000000
37    }
38    }
39    */
40 
41 public:
42   explicit LibstdcppMapIteratorSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp);
43 
44   size_t CalculateNumChildren() override;
45 
46   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
47 
48   bool Update() override;
49 
50   bool MightHaveChildren() override;
51 
52   size_t GetIndexOfChildWithName(ConstString name) override;
53 
54 private:
55   ExecutionContextRef m_exe_ctx_ref;
56   lldb::addr_t m_pair_address;
57   CompilerType m_pair_type;
58   lldb::ValueObjectSP m_pair_sp;
59 };
60 
61 class LibStdcppSharedPtrSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
62 public:
63   explicit LibStdcppSharedPtrSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp);
64 
65   size_t CalculateNumChildren() override;
66 
67   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
68 
69   bool Update() override;
70 
71   bool MightHaveChildren() override;
72 
73   size_t GetIndexOfChildWithName(ConstString name) override;
74 };
75 
76 } // end of anonymous namespace
77 
78 LibstdcppMapIteratorSyntheticFrontEnd::LibstdcppMapIteratorSyntheticFrontEnd(
79     lldb::ValueObjectSP valobj_sp)
80     : SyntheticChildrenFrontEnd(*valobj_sp), m_exe_ctx_ref(), m_pair_address(0),
81       m_pair_type(), m_pair_sp() {
82   if (valobj_sp)
83     Update();
84 }
85 
86 bool LibstdcppMapIteratorSyntheticFrontEnd::Update() {
87   ValueObjectSP valobj_sp = m_backend.GetSP();
88   if (!valobj_sp)
89     return false;
90 
91   TargetSP target_sp(valobj_sp->GetTargetSP());
92 
93   if (!target_sp)
94     return false;
95 
96   bool is_64bit = (target_sp->GetArchitecture().GetAddressByteSize() == 8);
97 
98   if (!valobj_sp)
99     return false;
100   m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
101 
102   ValueObjectSP _M_node_sp(
103       valobj_sp->GetChildMemberWithName(ConstString("_M_node"), true));
104   if (!_M_node_sp)
105     return false;
106 
107   m_pair_address = _M_node_sp->GetValueAsUnsigned(0);
108   if (m_pair_address == 0)
109     return false;
110 
111   m_pair_address += (is_64bit ? 32 : 16);
112 
113   CompilerType my_type(valobj_sp->GetCompilerType());
114   if (my_type.GetNumTemplateArguments() >= 1) {
115     CompilerType pair_type = my_type.GetTypeTemplateArgument(0);
116     if (!pair_type)
117       return false;
118     m_pair_type = pair_type;
119   } else
120     return false;
121 
122   return true;
123 }
124 
125 size_t LibstdcppMapIteratorSyntheticFrontEnd::CalculateNumChildren() {
126   return 2;
127 }
128 
129 lldb::ValueObjectSP
130 LibstdcppMapIteratorSyntheticFrontEnd::GetChildAtIndex(size_t idx) {
131   if (m_pair_address != 0 && m_pair_type) {
132     if (!m_pair_sp)
133       m_pair_sp = CreateValueObjectFromAddress("pair", m_pair_address,
134                                                m_exe_ctx_ref, m_pair_type);
135     if (m_pair_sp)
136       return m_pair_sp->GetChildAtIndex(idx, true);
137   }
138   return lldb::ValueObjectSP();
139 }
140 
141 bool LibstdcppMapIteratorSyntheticFrontEnd::MightHaveChildren() { return true; }
142 
143 size_t LibstdcppMapIteratorSyntheticFrontEnd::GetIndexOfChildWithName(
144     ConstString name) {
145   if (name == "first")
146     return 0;
147   if (name == "second")
148     return 1;
149   return UINT32_MAX;
150 }
151 
152 SyntheticChildrenFrontEnd *
153 lldb_private::formatters::LibstdcppMapIteratorSyntheticFrontEndCreator(
154     CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {
155   return (valobj_sp ? new LibstdcppMapIteratorSyntheticFrontEnd(valobj_sp)
156                     : nullptr);
157 }
158 
159 /*
160  (lldb) fr var ibeg --ptr-depth 1
161  (__gnu_cxx::__normal_iterator<int *, std::vector<int, std::allocator<int> > >)
162  ibeg = {
163  _M_current = 0x00000001001037a0 {
164  *_M_current = 1
165  }
166  }
167  */
168 
169 SyntheticChildrenFrontEnd *
170 lldb_private::formatters::LibStdcppVectorIteratorSyntheticFrontEndCreator(
171     CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {
172   static ConstString g_item_name;
173   if (!g_item_name)
174     g_item_name.SetCString("_M_current");
175   return (valobj_sp
176               ? new VectorIteratorSyntheticFrontEnd(valobj_sp, g_item_name)
177               : nullptr);
178 }
179 
180 lldb_private::formatters::VectorIteratorSyntheticFrontEnd::
181     VectorIteratorSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp,
182                                     ConstString item_name)
183     : SyntheticChildrenFrontEnd(*valobj_sp), m_exe_ctx_ref(),
184       m_item_name(item_name), m_item_sp() {
185   if (valobj_sp)
186     Update();
187 }
188 
189 bool VectorIteratorSyntheticFrontEnd::Update() {
190   m_item_sp.reset();
191 
192   ValueObjectSP valobj_sp = m_backend.GetSP();
193   if (!valobj_sp)
194     return false;
195 
196   if (!valobj_sp)
197     return false;
198 
199   ValueObjectSP item_ptr(valobj_sp->GetChildMemberWithName(m_item_name, true));
200   if (!item_ptr)
201     return false;
202   if (item_ptr->GetValueAsUnsigned(0) == 0)
203     return false;
204   Status err;
205   m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
206   m_item_sp = CreateValueObjectFromAddress(
207       "item", item_ptr->GetValueAsUnsigned(0), m_exe_ctx_ref,
208       item_ptr->GetCompilerType().GetPointeeType());
209   if (err.Fail())
210     m_item_sp.reset();
211   return false;
212 }
213 
214 size_t VectorIteratorSyntheticFrontEnd::CalculateNumChildren() { return 1; }
215 
216 lldb::ValueObjectSP
217 VectorIteratorSyntheticFrontEnd::GetChildAtIndex(size_t idx) {
218   if (idx == 0)
219     return m_item_sp;
220   return lldb::ValueObjectSP();
221 }
222 
223 bool VectorIteratorSyntheticFrontEnd::MightHaveChildren() { return true; }
224 
225 size_t VectorIteratorSyntheticFrontEnd::GetIndexOfChildWithName(
226     ConstString name) {
227   if (name == "item")
228     return 0;
229   return UINT32_MAX;
230 }
231 
232 bool lldb_private::formatters::LibStdcppStringSummaryProvider(
233     ValueObject &valobj, Stream &stream, const TypeSummaryOptions &options) {
234   const bool scalar_is_load_addr = true;
235   AddressType addr_type;
236   lldb::addr_t addr_of_string =
237       valobj.GetAddressOf(scalar_is_load_addr, &addr_type);
238   if (addr_of_string != LLDB_INVALID_ADDRESS) {
239     switch (addr_type) {
240     case eAddressTypeLoad: {
241       ProcessSP process_sp(valobj.GetProcessSP());
242       if (!process_sp)
243         return false;
244 
245       StringPrinter::ReadStringAndDumpToStreamOptions options(valobj);
246       Status error;
247       lldb::addr_t addr_of_data =
248           process_sp->ReadPointerFromMemory(addr_of_string, error);
249       if (error.Fail() || addr_of_data == 0 ||
250           addr_of_data == LLDB_INVALID_ADDRESS)
251         return false;
252       options.SetLocation(addr_of_data);
253       options.SetProcessSP(process_sp);
254       options.SetStream(&stream);
255       options.SetNeedsZeroTermination(false);
256       options.SetBinaryZeroIsTerminator(true);
257       lldb::addr_t size_of_data = process_sp->ReadPointerFromMemory(
258           addr_of_string + process_sp->GetAddressByteSize(), error);
259       if (error.Fail())
260         return false;
261       options.SetSourceSize(size_of_data);
262 
263       if (!StringPrinter::ReadStringAndDumpToStream<
264               StringPrinter::StringElementType::UTF8>(options)) {
265         stream.Printf("Summary Unavailable");
266         return true;
267       } else
268         return true;
269     } break;
270     case eAddressTypeHost:
271       break;
272     case eAddressTypeInvalid:
273     case eAddressTypeFile:
274       break;
275     }
276   }
277   return false;
278 }
279 
280 bool lldb_private::formatters::LibStdcppWStringSummaryProvider(
281     ValueObject &valobj, Stream &stream, const TypeSummaryOptions &options) {
282   const bool scalar_is_load_addr = true;
283   AddressType addr_type;
284   lldb::addr_t addr_of_string =
285       valobj.GetAddressOf(scalar_is_load_addr, &addr_type);
286   if (addr_of_string != LLDB_INVALID_ADDRESS) {
287     switch (addr_type) {
288     case eAddressTypeLoad: {
289       ProcessSP process_sp(valobj.GetProcessSP());
290       if (!process_sp)
291         return false;
292 
293       CompilerType wchar_compiler_type =
294           valobj.GetCompilerType().GetBasicTypeFromAST(lldb::eBasicTypeWChar);
295 
296       if (!wchar_compiler_type)
297         return false;
298 
299       // Safe to pass nullptr for exe_scope here.
300       llvm::Optional<uint64_t> size = wchar_compiler_type.GetBitSize(nullptr);
301       if (!size)
302         return false;
303       const uint32_t wchar_size = *size;
304 
305       StringPrinter::ReadStringAndDumpToStreamOptions options(valobj);
306       Status error;
307       lldb::addr_t addr_of_data =
308           process_sp->ReadPointerFromMemory(addr_of_string, error);
309       if (error.Fail() || addr_of_data == 0 ||
310           addr_of_data == LLDB_INVALID_ADDRESS)
311         return false;
312       options.SetLocation(addr_of_data);
313       options.SetProcessSP(process_sp);
314       options.SetStream(&stream);
315       options.SetNeedsZeroTermination(false);
316       options.SetBinaryZeroIsTerminator(false);
317       lldb::addr_t size_of_data = process_sp->ReadPointerFromMemory(
318           addr_of_string + process_sp->GetAddressByteSize(), error);
319       if (error.Fail())
320         return false;
321       options.SetSourceSize(size_of_data);
322       options.SetPrefixToken("L");
323 
324       switch (wchar_size) {
325       case 8:
326         return StringPrinter::ReadStringAndDumpToStream<
327             StringPrinter::StringElementType::UTF8>(options);
328       case 16:
329         return StringPrinter::ReadStringAndDumpToStream<
330             StringPrinter::StringElementType::UTF16>(options);
331       case 32:
332         return StringPrinter::ReadStringAndDumpToStream<
333             StringPrinter::StringElementType::UTF32>(options);
334       default:
335         stream.Printf("size for wchar_t is not valid");
336         return true;
337       }
338       return true;
339     } break;
340     case eAddressTypeHost:
341       break;
342     case eAddressTypeInvalid:
343     case eAddressTypeFile:
344       break;
345     }
346   }
347   return false;
348 }
349 
350 LibStdcppSharedPtrSyntheticFrontEnd::LibStdcppSharedPtrSyntheticFrontEnd(
351     lldb::ValueObjectSP valobj_sp)
352     : SyntheticChildrenFrontEnd(*valobj_sp) {
353   if (valobj_sp)
354     Update();
355 }
356 
357 size_t LibStdcppSharedPtrSyntheticFrontEnd::CalculateNumChildren() { return 1; }
358 
359 lldb::ValueObjectSP
360 LibStdcppSharedPtrSyntheticFrontEnd::GetChildAtIndex(size_t idx) {
361   ValueObjectSP valobj_sp = m_backend.GetSP();
362   if (!valobj_sp)
363     return lldb::ValueObjectSP();
364 
365   if (idx == 0)
366     return valobj_sp->GetChildMemberWithName(ConstString("_M_ptr"), true);
367   else
368     return lldb::ValueObjectSP();
369 }
370 
371 bool LibStdcppSharedPtrSyntheticFrontEnd::Update() { return false; }
372 
373 bool LibStdcppSharedPtrSyntheticFrontEnd::MightHaveChildren() { return true; }
374 
375 size_t LibStdcppSharedPtrSyntheticFrontEnd::GetIndexOfChildWithName(
376     ConstString name) {
377   if (name == "_M_ptr")
378     return 0;
379   return UINT32_MAX;
380 }
381 
382 SyntheticChildrenFrontEnd *
383 lldb_private::formatters::LibStdcppSharedPtrSyntheticFrontEndCreator(
384     CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {
385   return (valobj_sp ? new LibStdcppSharedPtrSyntheticFrontEnd(valobj_sp)
386                     : nullptr);
387 }
388 
389 bool lldb_private::formatters::LibStdcppSmartPointerSummaryProvider(
390     ValueObject &valobj, Stream &stream, const TypeSummaryOptions &options) {
391   ValueObjectSP valobj_sp(valobj.GetNonSyntheticValue());
392   if (!valobj_sp)
393     return false;
394 
395   ValueObjectSP ptr_sp(
396       valobj_sp->GetChildMemberWithName(ConstString("_M_ptr"), true));
397   if (!ptr_sp)
398     return false;
399 
400   ValueObjectSP usecount_sp(valobj_sp->GetChildAtNamePath(
401       {ConstString("_M_refcount"), ConstString("_M_pi"),
402        ConstString("_M_use_count")}));
403   if (!usecount_sp)
404     return false;
405 
406   if (ptr_sp->GetValueAsUnsigned(0) == 0 ||
407       usecount_sp->GetValueAsUnsigned(0) == 0) {
408     stream.Printf("nullptr");
409     return true;
410   }
411 
412   Status error;
413   ValueObjectSP pointee_sp = ptr_sp->Dereference(error);
414   if (pointee_sp && error.Success()) {
415     if (pointee_sp->DumpPrintableRepresentation(
416             stream, ValueObject::eValueObjectRepresentationStyleSummary,
417             lldb::eFormatInvalid,
418             ValueObject::PrintableRepresentationSpecialCases::eDisable,
419             false)) {
420       return true;
421     }
422   }
423 
424   stream.Printf("ptr = 0x%" PRIx64, ptr_sp->GetValueAsUnsigned(0));
425   return true;
426 }
427